The full history of technological change also involves several social and economic conditions.
First, changes in implements, tools, and methods result from the accumulation of knowledge. Device builds upon device: first came the wheel, and then, much later, the tractor.
Secondly, the potential user of the device must feel a need for it. The new method or device not only must save him work but must clearly increase his well-being. If any device or change merely increases the wealth of someone else (a tax collector or a landlord for example), the farmer seldom will adopt the new technology.
Thirdly, since, at first, the new technology almost invariably costs more than the old, the user must have or be able to get the capital to buy and use the newer devices and methods.
Of these conditions for technological change, only the cumulative nature of the knowledge can be shown by the objects. Even here, however, missing objects make it possible to present only the most obvious changes, and then not all of them. Still, seeing the things once used—no matter how crude or how few—can sometimes help us understand the way changes took place. Also, this knowledge sometimes can help us guess how other changes will take place:
The sequence of inventions also depends upon the changing needs of a society. Needs and circumstances vary more than do degrees of talent. Thus when need and knowledge merge, inventors quickly appear. Indeed, several men in several places are likely to work on the same problems at the same time, and they often solve it in almost identical fashion. Nearly simultaneous inventions or discoveries occur with astonishing frequency in the history of technology.[2]
[2]"The Combine Made in Stockton," Pacific Historian, no. 10 (Autumn, 1966), p. 14.
The Use of Farm Machinery in America
The part of America that was destined to become the United States started its history at the very time when the parent European civilization began to make major breakthroughs in science and technology. Thus, Americans became the automatic beneficiaries of the achievements of others. Because of peculiar opportunities and needs, Americans could and did push on to unique achievements. Nowhere, however, did this building on the past appear as early, or as impressively, as in the agricultural sector of the economy. American inventors of farm implements made important strides earlier than those in any other field. In turn, American farmers made more and better use of discoveries and inventions.